Radiosynthesis of carbon-11-labeled camptothecin derivatives as potential positron emission tomography tracers for imaging of topoisomerase I in cancers.

Department of Radiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Bioorganic & Medicinal Chemistry Letters (Impact Factor: 2.34). 10/2005; 15(17):3865-9. DOI: 10.1016/j.bmcl.2005.05.108
Source: PubMed

ABSTRACT Four carbon-11-labeled camptothecin derivatives, 9-[11C]methoxy-20(S)-camptothecin ([11C]5), 10-[11C]methoxy-20(S)-camptothecin ([11C]7), 9-nitro-10-[11C]methoxy-20(S)-camptothecin ([11C]9), and 9-[([11C]trimethylamino)methyl]-10-hydroxy-20(S)-camptothecin ([11C]11), have been synthesized as potential positron emission tomography tracers for imaging of topoisomerase I in cancers.

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